PROJECT DESCRIPTION:

This research project investigates human and social behavior for emergency exits in buildings and facilities. Among the numerous regulatory provisions governing a facility design, one of the key issues identified by facility managers and building inspectors is safe egress. Design of egress for places of public assembly is a formidable problem in facility and safety engineering. There have been numerous incidents reported regarding overcrowding and crushing during emergency situations. Such incidents occur in sport stadiums (for example, the stampede incident in a soccer stadium that killed over 120 people in Ghana, Africa, 2001), schools (for example, the incident due to power outage that killed 21 children and injured 47 in Beijing, China, 2002), social gathering places (for example, the incident at a nightclub in Chicago, IL in 2003 that killed 21 people) and religious worships (for example, the incident in Mecca, Saudi Arabia that killed over 240 people in 2004). In addition to injuries and loss of lives, the accompanying post-disaster psychological suffering, financial loss, and adverse publicity have long-term negative effects on related individuals and organizations - the survivors, the victims’ families, and the local communities [1].

Studies to improve crowd safety in places of public assembly involve many disciplines: architectural design for safe egress [2, 3, 4], crowd planning and management [5], crowd simulations [6, 7], emergency planning, leadership training and many others [8]. Even for well planned events in well designed facilities, an undeniable fact is that real danger lies within the crowds. In a crowded environment, it has been observed that most victims were injured or killed by the so called “non-adaptive” behaviors of the crowd, rather than the actual cause (such as fire or explosion) of the disaster. For example, in the Iroquois Theatre fire (in 1903), the initial fire was brought under control quickly; however, 602 people were trampled to death in the end. Another example is the Hillsborough English FA Cup Stampede (in 1981); there were no real causes of emergency but still 95 people died and over 400 people were injured.

Non-adaptive crowd behaviors refer to the destructive actions that a crowd may experience in emergency situations, such as stampede, pushing others out of the way, knocking others down, and trampling on others, etc.; these actions are responsible for a large number of injuries and deaths in man-made and natural disasters. To study non-adaptive behavior in a crowded environment, we need to carefully study human and social behavior in panic situation from both psychological and sociological perspectives. On a microscopic level, individuals in a crowd act and make decisions differently than when they are alone or in a small group. On a macroscopic level, non-adaptive crowd behaviors are collective phenomena triggered by some external crises or emergencies (e.g., fire, smoke, or explosion). Surprisingly, there have been very few studies focusing on non-adaptive crowd behaviors from psychological and sociological perspectives in the area of facility and safety engineering.

Building codes contain “means of egress” provisions designed to ensure the safety of a building. However, these codes only provide basic guidelines and are not exhaustive and often insufficient for many practical situations. First, current codes and guidelines contain inconsistencies which may lead to misinterpretations. An effective tool is needed to test whether a specific guideline is appropriate for a particular situation. Second, each building is unique, and compliance with design guidelines does not automatically ensure safety. Often, local geometries – shapes and sizes of spaces and obstacles – can have significant influence to egress, albeit in a subtle way. To date, very few studies can be found in existing literature in terms of understanding how environmental constraints and local geometries impact the crowd behaviors and movements. This type of studies is difficult since it often requires exposing real people to the actual, possibly dangerous, environment. A good computational tool which takes into consideration of human and social behavior of a crowd could serve as a viable alternative.

Commercially available computational tools for the simulation and design of emergency exits exist. However, most of the current computational tools focus on the modeling of spaces and occupancies but rarely take into consideration of crowd behavior. On the other hand, the usefulness of a simulation tool is preconditioned by its ability to model properly and correctly the crowd and their behaviors. Understanding non-adaptive crowd behaviors is essential to the development of effective egress strategies and models for achieving safety. None of the current models have been able to cover the range of scenarios suitable for safety engineering purpose [9]. These models either are oversimplified or are based on incorrect assumptions about crowd behaviors. As noted in a recent report by the Society of Fire Protection Engineers [10], “These (computational) models are attractive because they seem to more accurately simulate evacuations. However, due to the scarcity of behavioral data, they tend to rely heavily on assumptions and it is not possible to gauge with confidence their predictive accuracy.”

In this research, we will study non-adaptive crowd behaviors from the perspectives of human behavior and social interactions and to incorporate such behaviors in a dynamic computational model suitable for the analysis and design of safe egress. The computational model will be able to adapt egress analysis suitable for specific design circumstances. Furthermore, the behavior-based model will provide insight to current prescriptive and, often, ambiguous codes and provisions for egress design. The computational tool also can serve as a means to study safety engineering, such as assessing building codes and designs, testing safety and evacuation procedures, and crowd management.

REFERENCES:

[1]. Lystad, M., Mental Health Response to Mass Emergencies: Theory and Practice, Brunner/Mazel, New York, 1988.

[2]. Greenwood, T., Guide to Fire Precautions in Existing Places of Entertainment and Like Premise, HMSO, London, 1998. (ISBN 0113409079)

[3]. Helbing, D., Farkas, I., and Vicsek, T., “Simulating Dynamical Features of Escape Panic,” Nature, 407:487-490, 2000.

[4]. Han, C.S., Kunz, J. and Law, K.H., “A Hybrid Prescriptive/Performance Based Approach to Automated Building Code Checking,” International Computing Congress, ASCE, pp. 537-548, Boston, MA, October, 1998.

[5]. City of Cincinnati, Crowd Management: Report of the Task Force on Crowd Control and Safety, Technical Report, 1980. Available at http://www.crowdsafe.com/taskrpt/ whocrowdmanagementstaffandcontentspages.pdf.

[6]. AEA Technology, A Technical Summary of the AEA EGRESS Code, Technical Report, AEAT/NOIL/27812001/002(R), Issue 1, available at http://www.aeat-safety-and-risk.com/Downloads/Egress%20Technical%20Summary.pdf, 2002.

[7]. Fire Safety Engineering Group, BuildingEXODUS: the evacuation Model for the Building Environment, available at http://fseg.gre.ac.uk/exodus/air.html#build, September, 2003.

[8]. Chertkoff, J. and Kushigian, R., Don’t Panic: The Psychology of Emergency Egress and Ingress, Praeger, London, 1999.

[9]. Still, G., Crowd Dynamics, Ph.D. thesis, University of Warwick, UK, 2000.

[10]. Society of Fire Protection Engineers, Engineering Guide to Human Behavior in Fire, Technical Report, 2002. Available at http://www.sfpe.org/sfpe/pdfsanddocs/DraftHumanBehaviorGuide.pdf.

If you have any comments or suggestions, please send them to xpan@stanford.edu